JP5802542B2 - Sanda - Google Patents

Description

  The present invention relates to a sander having a fan.

  As shown in the following Patent Document 1, a sander having a dust collecting and cooling fan is known. In this sander, the fan is attached to a rotating shaft of a motor that drives a pad below the sander.

JP-A-6-226709

  In the sander of Patent Document 1, since the fan is directly attached to the rotating shaft at the lower part of the motor, the motor has to be arranged on the upper center side of the fan, and the total height tends to increase. In addition, since the fan is attached to the rotating shaft of the motor, the fan becomes a set with the motor and the arrangement of these is restricted. When the fan is enlarged, there is a space outside the motor body (above the fan side edge). As a result, the outer dimensions are large, and if downsizing is emphasized, the size of the fan is restricted, and the dust collection capacity and cooling capacity (fan efficiency) are limited.

  Therefore, the main object of the present invention is to provide a sander that has less restrictions on the arrangement of the motor and the fan, can be downsized while ensuring a sufficient fan efficiency without increasing the size of the fan.

In order to achieve the above object, an invention according to claim 1 has a motor for driving a pad, and in a sander having an upper portion as a gripping portion, an output shaft to which the pad is attached is provided in the motor. Provided separately from the rotating shaft, the output shaft and the rotating shaft are connected via a speed reducing mechanism that transmits the latter rotation to the former while decelerating, and a fan is provided on the output shaft. The speed reduction member constituting the speed reduction mechanism is provided with a vent hole .
According to a second aspect of the present invention, in the above invention, the speed reduction member is provided on the output shaft.
The invention described in claim 3 is characterized in that, in the above-mentioned invention, the fan is provided with a balance portion for adjusting a rotation mode of the pad.
The invention according to claim 4 is characterized in that, in the above-mentioned invention, a side portion of the fan in the housing is a protruding portion projecting from the periphery.

According to the first aspect of the present invention, the fan is provided on the output shaft connected to the rotating shaft of the motor via the speed reduction mechanism, so that the center of the motor and the fan is not arranged vertically. The height can be suppressed by arranging a motor above the peripheral edge of the fan, etc., and the sander with the upper portion, which is generally required to be compact, can be made sufficiently compact. Also, since it is not necessary to align the center of the motor and the fan, even if the fan is enlarged, it is not necessary to evenly project from the lower side of the motor side circumference, and the fan is enlarged and the fan efficiency is improved while maintaining compactness. It can be. Furthermore, the relationship between the motor output and the rotational torque of the fan can be adjusted by the speed reduction mechanism. With an emphasis on compactness, while using a motor with a relatively weak output, the fan speed can be sufficient, In order to place importance on efficiency, the degree of freedom of design can be increased, for example, even if a fan having a relatively large diameter and a large weight is employed, the output shaft can be sufficiently driven by deceleration. Since the speed reducing member is provided with a vent hole, in addition to the above effect, the air generated by the fan can be smoothly passed, and the efficiency of cooling and the like can be improved.
Furthermore, according to the second aspect of the invention, since the ventilation hole is provided in the speed reduction member on the output shaft, in addition to the above effects, it is possible to suppress the shielding of the wind by the speed reduction member disposed at the center inside the sander. And the efficiency of cooling and the like can be made still better.
Furthermore, according to the invention described in claim 3 , since the balance portion is provided in the fan, in addition to the above effects, the fan can also play a role such as a counterweight, and the rotation of the pad can be stabilized. The whole can be made compact compared with the case where a counterweight is provided separately.
Further, according to the invention described in claim 4 , since the housing part outside the fan is projected, in addition to the above effects, the parts other than the projected part that is projected are constricted to be easily grasped or made compact. In addition, a hand to be slid can be stopped by the projecting part when the part other than the projecting part is gripped, and the operation can be performed stably and reliably.

It is a partially notched top view of the sander which concerns on this invention. FIG. 2 is a transverse center sectional view of FIG. 1. It is a figure which shows the cross section containing the axis line of the output shaft in FIG. It is the (a) perspective view, (b) top view, (c) bottom view of the pulley in the sander of FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a partially cutaway plan view of the sander 1 (the right side of the figure is the front of the sander 1), and FIG. 2 is a transverse central sectional view of FIG.
The sander 1 is a palm type that can be operated by gripping the upper part 2a (gripping part) of the housing 2 with one hand of the user, and includes buttons 3a and 3b on the side of the upper part 2a.

  Further, the sander 1 is provided with a vertical output shaft 4 in a central portion in the housing 2 so as to be rotatable around the central axis. Ball bearings 6 and 7 are respectively arranged around the upper part and the center part of the output shaft 4, and these are fixed to the housing 2 inside the housing 2.

In addition, an output shaft side pulley 8 as one of the speed reducing members constituting the speed reducing mechanism is fixed around the central portion of the output shaft 4 (below the ball bearing 7), and further around the lower side thereof. The fan 9 is fixed.
The fan 9 is a disk-like member that is entirely horizontal, and on one side, a plurality of upwardly projecting blade portions 9c, 9c,. A thick portion 9e in which the outer tip portions of several blade portions 9c, 9c,.
Similarly, a plurality of downwardly projecting blade portions 9d, 9d,... That extend radially from the center to the periphery are formed on the other side, and a portion of the periphery is point-symmetric with the thick portion 9e. A thick portion 9f is formed.
The blade portions 9d, 9d,... Are relatively short on the inner side of the blade portions 9c, 9c,..., Creating a space for the pad bearing tool 14 including the ball bearing 16 and the like to be compacted in the vertical direction. It contributes to.
The fan 9 housing portion in the lower portion of the housing 2 is formed as projecting portions 2c and 2c that project from both sides to the upper side. Windows 2d and 2d for exhausting the fan 9 are opened on the side surface of each protrusion 2c. The upper part of each projecting part 2 c becomes a constricted part 44 that is recessed with respect to the periphery, and the constricted part 44 continues to the lower side of each side of the upper part 2 a of the housing 2.
In addition, a connection part 2b with a dust collection pipe 9a for discharging dust-containing air is formed in the lower part of the housing 2 and on the side of the fan 9 (below the battery mounting part 42 described later). The dust collection tube 9a is fixed at the connection portion 2b by a connection screw 9b. A plurality of ventilation windows 2e, 2e,... Are opened on both sides of the upper portion 2a of the housing 2, respectively.

FIG. 3 is a view showing a cross section including the axis of the output shaft 4 in FIG.
A pad 10 is attached to the tip of the output shaft 4, and a sanding paper for polishing (not shown) as an example of a tool is attached to the lower surface of the pad 10 via a surface fastener or the like.
The pad 10 includes a pad main body 12 and a pad bearing tool 14 disposed on the upper side thereof. The pad bearing device 14 includes a ball bearing 16, an inner bearing retainer 18 (flat washer) fixed to the inner cylinder, and an outer bearing retainer 20 fixed to the outer cylinder of the ball bearing 16.
In the inner bearing retainer 18, a hole through which the inner screw 22 entering the distal end portion of the output shaft 4 passes is formed at a position eccentric from the rotation axis of the ball bearing 16. The inner bearing retainer 18 is disposed below the inner cylinder of the ball bearing 16 and supports the ball bearing 16 from below. A lower protruding portion of the fan 9 is placed inside the inner cylinder of the ball bearing 16, and the output shaft 4 is passed through the lower protruding portion.
On the other hand, a hole for passing the outer screw 24 connecting the outer bearing retainer 20 and the pad main body 12 is formed in both of them.

  The thick portions 9e and 9f of the fan 9 are arranged as weights (weights) at the above-mentioned positions in consideration of the eccentric state of the pad 10, and adjust rotation and eccentric rotation (orbital rotation) of the pad 10 by the ball bearing 16 and the like. It plays the role of counterweight.

A motor 30 is fixed beside the output shaft 4 in the housing 2.
A motor-side pulley 34 as one of the speed reduction members is fixed to the rotating shaft 32 of the motor 30, and a belt (not shown) as one of the speed reduction members (not shown) is attached to the motor-side pulley 34 and the output shaft-side pulley 8. Timing belt) is hung. The motor-side pulley 34 has a smaller diameter than the output shaft-side pulley 8, and the rotation of the rotating shaft 32 is decelerated on the output shaft 4.

Further, a battery 40 is mounted outside the housing 2 on the opposite side of the motor 30 with the upper portion 2a or the output shaft 4 interposed therebetween. That is, the motor 30 is disposed on the opposite side of the battery 40 with the gripping part or the output shaft 4 interposed therebetween.
The battery 40 has a chamfered rectangular parallelepiped shape, and one or a plurality of terminals (not shown) are arranged on one surface.
The battery 40 is a rechargeable battery that can be charged by a charger, and the sander 1 is a rechargeable sander. Further, the buttons 3a and 3b are electrically connected to the motor 30 or the battery 40 so as to serve as switches.

The outer surface of the housing 2 opposite to the motor 30 is formed as a battery mounting portion 42 having a shape corresponding to the terminal surface of the battery 40.
The battery mounting portion 42 is inclined so as to enter the inner side as it goes downward so that the battery 40 is inclined and guided away from the axis of the output shaft 4 (upper and lower sides of the sander 1). That is, the battery 40 can be attached and detached by sliding it according to the inclination angle of the battery mounting portion 42. The battery mounting portion 42 includes a locking portion for the battery 40 (not shown). The locking portion is locked to the battery 40 when the battery 40 is mounted, and the locking portion is locked when the battery 40 is removed. The battery 40 is detachably received by being released. Further, the battery mounting portion 42 is provided with a terminal (not shown) that overlaps the terminal when the battery 40 is mounted. The terminal is electrically connected to the motor 30, and can supply the electric power of the mounted battery 40 to the motor 30.

The battery 40 attached to the battery attachment portion 42 becomes closer to the center of the sander 1 (housing 2) as it goes downward (a state where it goes inward as it goes downward). Further, the pad 10 (contact portion), the battery 40, or the battery mounting portion 42 are formed so that the lower portion of the mounted battery 40 enters inside from above the end of the pad 10 (contact portion).
Further, when the battery 40 is mounted, the battery 40 or the battery mounting portion 42 is formed so that the upper portion thereof is continuously aligned with the upper portion 2 a of the housing 2.

As shown in FIG. 4, the output shaft side pulley 8 is positioned on the lower outer side of the entire ring-shaped tooth portion 51 having a plurality of teeth 50, 50. And a plurality of columnar portions 54, 54... Connecting the inner side of the tooth portion 51 or the outer side of the central hole portion 53. A portion surrounded by the tooth portion 51 and the columnar portions 54 and 54 (and the central hole portion 53) is formed as vent holes 55, 55... And the output shaft side pulley 8 has a plurality of vent holes 55, 55. It has become a thing.
By opening the vent holes 55, 55,..., The output shaft side pulley 8 can vent air up and down.

Such a sander 1 operates as follows, for example.
That is, when the battery 40 is mounted on the battery mounting portion 42 and the button 3b is pressed while the operation is stopped, the battery 40 supplies power to the motor 30 and the rotating shaft 32 rotates at a predetermined speed. When the button 3a is pressed, the power supply by the battery 40 is cut off, the motor 30 is stopped and the operation is stopped, and when the button 3a is pressed (several times) during operation, the speed of the rotary shaft 32 is (sequentially in several types). Be changed.

The rotating shaft 32 of the motor 30 rotationally drives the output shaft 4 via the motor side pulley 34 fixed to the motor 30 and the belt or the output shaft side pulley 8.
By rotation of the output shaft 4, the pad 10 rotates as follows and rotates eccentrically. That is, the pad body 12 rotates around the ball bearings 6 and 7 and the output shaft 4 via the ball bearing 16 and the outer bearing retainer 20 (revolution). During the operation of the sander 1, a rolling resistance is generated by applying force between the inner cylinder, ball, and outer cylinder of the ball bearing 16, and the pad 10 rotates about the ball bearing 16 in the same direction as the revolution. Do (spin). In addition, at the time of no-load rotation, since the frictional resistance in the ball bearing 16 is in an unstable state, it may rotate irregularly or not rotate.
The pad 10 thus rotated is moved while being pressed against the work by grasping the upper portion 2a of the housing 2, whereby the surface of the work can be polished through sanding paper or the like.
The upper part 2 a of the housing 2 is sufficiently secured by the inclined mounting of the battery 40. In addition, due to the inclined mounting of the battery 40, the center of gravity of the sander 1 becomes closer to the center than when the battery 40 is not inclined. Such securing of the gripping portion and disposition near the center of the center of gravity can be realized by making the mounting angle of the battery 40 exceed 0 ° from the vertical line. Further, if the battery 40 is tilted too much, the device size of the sander 1 becomes too large and it becomes difficult to take up space for the internal structure. Therefore, the mounting angle is preferably within 30 ° from the vertical line. Even when the mounting angle of the battery 40 (longitudinal direction of extension) is set to 0 ° from the vertical line, the effect of securing the gripping portion and the center of the center of gravity is exhibited. What is necessary is just to extend to 0 degree or more with respect to a perpendicular direction.

Further, the fan 9 is rotated by the rotation of the output shaft 4. The air in the housing 2 is collected by the fan 9 by the blade portions 9c, 9d,... Of the fan 9, and is discharged to the windows 2d, 2d,. Due to the suction by the rotation of the fan 9, air is introduced into the housing 2 from the ventilation windows 2 e, 2 e.
Therefore, if the rotation of the fan 9 continues, air passes from the ventilation windows 2e, 2e,... Around the motor 30 and the output shaft 4, and further through the periphery of the output shaft side pulley 8 and the ventilation holes 55, 55,. It continues to flow through the blades 9c, 9d,... To the windows 2d, 2d,.
Thus, the air flowing from the upper part to the lower part in the housing 2 cools the internal mechanism such as the motor 30 and blows away dust if it adheres thereto. Such air travels toward the output shaft side pulley 8 located in the center of the housing 2, but the output shaft side pulley 8 is provided with vent holes 55, 55. -It can pass through and can move smoothly.
In particular, in the sander 1, in order to decelerate the rotation of the motor 30, it is necessary to make the diameter of the output shaft side pulley 8 larger than the diameter of the motor side pulley 34, and the output shaft side pulley 8 is aligned with the output shaft 4. 1, if there is no vent hole 55, 55..., The output shaft side pulley 8 greatly hinders the air flowing up and down in the housing 2, but the vent hole 55, 55. If provided, the flow will not be hindered, and the effect when the vent holes 55, 55,.
In addition, the air containing dust is discharged | emitted through the connection part 2b by the dust collection pipe | tube 9a.

In the sander 1 described above, the upper portion 2a of the housing 2 is a gripping portion, and the battery mounting portion 42 approaches the output shaft 4 (center portion of the sander 1) as it goes downward (enters inside). ) Since the battery 40 is tilted so as to be farther away (outward), the battery 40 is similarly mounted in a tilted state. At this time, the longitudinal direction of the long battery 40 is extended at an angle exceeding 0 ° in the direction entering the inner side as it goes downward with respect to the vertical direction.
Therefore, the battery 40 which is relatively heavy can be brought close to the output shaft 4 in the center of the sander 1 while taking a wide gripping portion, and the center of gravity of the sander 1 is secured while ensuring a sufficient space for the grip of the sander 1. The position can be moved to the center to improve the stability. Therefore, the ease of gripping and the center of gravity position closer to the center can improve the operability by making it easy to move, and even if vibration occurs during the operation of the sander 1, the influence of the center of gravity position can be reduced. And stability can be improved.

In addition, since the motor 30 is arranged on the opposite side across the grip portion of the battery 40, the relatively heavy motor 30 can be disposed opposite to the relatively heavy battery 40, The operability and stability can be further improved with a good weight balance.
Further, the rotation of the motor 30 is decelerated at the output shaft 4 and the pad 10 is rotated and eccentrically rotated (orbital rotation), so that it is exchanged for better performance, such as improved polishing accuracy, compared to those without orbital rotation. However, since the weight balance is improved by the diagonal installation of the battery 40, the vibration can be effectively dealt with by improving the operability and stability.

Furthermore, since the lower part of the battery 30 is located inside the upper end of the pad 10, the weight of the battery 40 can be applied almost vertically to the pad 10 via the output shaft 4. It is possible to effectively cope with vibrations and the like caused by a reaction force received from the pad 10 by such a weight balance.
Also, by setting the battery 40 mounting angle to be within the range of more than 0 ° and not more than 30 °, sufficient space for the internal structure can be secured while realizing a sufficient holding portion and an appropriate weight balance. The sander 1 can be made compact.
In addition, when the battery 40 is mounted, its height is aligned with the gripping portion, so that it is possible to prevent the battery 40 from interfering with the arm, etc. Can also be placed).

In the sander 1, the output shaft 4 is not directly connected to the rotating shaft 32 of the motor 30, but is connected to the rotating shaft 32 via the output shaft side pulley 8, the motor side pulley 34, and the speed reduction mechanism including the belt. The fan 9 is fixed to the output shaft 4. When the fan 9 is provided in this way, the motor 30, the rotary shaft 32, the output shaft 4 or its ball bearings 6, 7, and the fan 9 are not arranged vertically, as in the case where the fan 9 is directly attached to the rotary shaft 32. It can be divided into left and right sides on the output side and the output shaft 4 side. Therefore, the internal mechanism of the sander 1 does not increase in the vertical direction, and the sander 1 can be made compact with a low height. In particular, the palm-type sander 1 having a grip portion on the upper part is easy to grip. It can be easily moved and adapted to the mold.
Further, in the sander 1 in which the rotating shaft 32 and the output shaft 4 with the fan 9 are connected via a speed reduction mechanism, the sander 1 does not protrude greatly to the side as compared with the case where the fan 9 is directly provided on the rotating shaft 32. The fan 9 can be enlarged. That is, since it is not necessary to make the center of the fan 9 coincide with the rotation shaft 32 at the center of the motor 30, the periphery of the fan 9 can be arranged below the motor 30, and the fan 9 can be made larger without projecting sideways. can do. As described above, the fan 9 can be sufficiently enlarged while maintaining the overall compactness, and thus the fan 9 can be made highly efficient. The fan efficiency is lower than that when the fan 9 is directly provided on the rotating shaft 32, but the rotational speed of the fan 9 is lowered and reduced accordingly. However, the efficiency of the fan 9 is increased. As a result of the increase, the decrease can be sufficiently covered, and sufficient wind can be generated for cooling the sander 1 or the like.

  Further, since the output shaft side pulley 8 is provided with vent holes 55, 55,..., The air moved by the fan 9 can be passed through the vent holes 55, 55,. In the output shaft side pulley 8 arranged in the center of the inside, air flow is smoothed without hindering air flow, and cooling and the like are efficiently performed.

  Further, since the fan 9 has thick portions 9e and 9f (balance portions) that increase the weight of the installation portion at the side periphery, the rotation mode of the pad 10 by the output shaft 4 depends on the arrangement or weight of the thick portions 9e and 9f. It can be adjusted (counterweight), and the rotation can be adjusted particularly effectively for the pad 10 that performs relatively complicated orbital rotation.

In addition, since the projecting portions 2c and 2c are projected on the outer portion of the fan 9 in the housing 2 so as to correspond to the arrangement of the fan 9, the fan 9 is not enlarged without increasing the size of the sander 1 as a whole. it can fit a while easily grasping by the constricted portion 44 to the outside of the projecting portion 2c, it is possible to stop the slipping of the hand when gripping by the constricted portion 44 by the protruding portion 2c. In particular, if the protruding portion 2c is disposed below the constricted portion 44, the fan 9 can be disposed at a position adjacent to the pad 10, and a situation in which the hand slips toward the pad 10 can be prevented.

  In addition, this invention is not limited to the said form, It has the modification shown next, respectively. The ventilation hole is provided in at least one member of another internal mechanism instead of or together with the output shaft side pulley. By providing a vent hole in the internal member in this way, air permeability can be improved even in that portion, and in particular, if a vent hole is provided in the motor side pulley, the motor located in the periphery of the output shaft side pulley, that is, in the center of the inside. Wind can be passed more smoothly through the side pulleys, and the cooling operation and the like by the fan can be improved.

In addition, the ventilation holes may be singular, increase / decrease, change the shape (circularity, etc.), size, arrangement (asymmetry, etc.), or change the shape and size of some of the plurality of holes. For fans, change the shape and number of the blades and thick parts, give the part of the blades the function of the thick part (balance part), or give only the ventilation function and do not consider the weight. Or, fix the output shaft directly without inserting the lower center of the fan into the inner cylinder of the ball bearing of the pad.

  For the battery mounting mode, instead of the slide mounting method guided to the battery mounting portion, a direct mounting method for directly locking to the locking portion is adopted, or a box-shaped housing portion with or without a lid is provided. A method of mounting the battery by housing is adopted. Omit battery latches, fans, dust collection tubes, etc., increase or decrease the number of various bearings, screws, and buttons. In the sander with buttons for various modes switching and on / off, lever switches instead of buttons, belts and pulleys with gears (with vents), screws as pins, and batteries The function, arrangement, type, and number of various members are changed as appropriate, such as making the rechargeable battery rechargeable, adopting a fully used battery, and increasing / decreasing the number of protruding or constricted portions and various windows of the housing. Further, the present invention is applied to a sander other than the orbital sander in which the pad rotates orbitally.

  1. ・ Sander, 2. ・ Housing, 2a ・ ・ (Housing) upper part (gripping part), 2c ・ ・ (Housing) projecting part, 4. ・ Output shaft, 8. ・ Output shaft side pulley (reduction member) .. 9 .. Fan, 9 e, 9 f .. Thick part (balance part) of (fan), 10 .. Pad, 30 .. Motor, 32 .. Rotating shaft of (motor), 40 .. Battery, 42.・ Battery mounting part, 44 .. (container) constriction part, 55.

Claims (4)

In the sander that has a motor to drive the pad and the upper part is a gripping part,
The output shaft to which the pad is attached is provided separately from the rotating shaft of the motor,
The output shaft and the rotation shaft are connected via a speed reduction mechanism that transmits the latter rotation to the former at a reduced speed,
A fan is provided on the output shaft ,
A sander, wherein a ventilation hole is provided in a speed reduction member constituting the speed reduction mechanism . The sander according to claim 1 , wherein the speed reduction member is provided on the output shaft. The fan, sander according to claim 1 or claim 2, characterized in that the balance unit for adjusting the rotational mode of the pad is provided. The sander according to any one of claims 1 to 3 , wherein a side portion of the fan in the housing is a projecting portion protruding to the periphery.

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